When a lock is mounted in a door, a hatch or the like, it is a desire that the abutment surface of its locking bolt, when in its locking position, shall be as close as possible to a counter-surface associated to, e.g., a door post or the like. Evidently, this is because an increased spacing between the abutment surface and the counter-surface allows a certain degree of movement of the door, and, thus, possible noise due to such movement.